Electric water heater of the storage type



arch 29 1927. A. E. LEWIS ELECTRIC WATER HEATER OF THE STORAGE TYPEFiled Dec. 17, 1925 vi i; FL J1 flit Lam s Patented Mar. 29, 1927.

Airsa IeE t C M E WN e v e erm ne LE W ve se seems IKE STORAGE TYPE-Application filed December 17, 1925, Serial No. 75,079, and in AustraliaJanuary 14, 1925.

This invention is intended for use where a comparatively large quantityof hot water is required at one time, as for instance in the case ofbaths.

In one form it consists of a jacketed tank with a suitableinsulatingmaterial filled into the space between the tank and thejacket. The tank is surroundedby a coil, preferably of copper pipe, thelower end of which is connected through the jacket, to a source ofwatersupply, the upper end passing into the tank and terminating in a .fioatcontrolled valve. The draw ofi": pipe is connected near the bottom, ofthe tank, passes through the jacket and will be controlled. by asuitable cock. The jacketed tank is preferably provided with a jacketedcover in which is a central Qopening. 'llhrough the central opening inthe cover an earthenware or other non-electric conducting vcssel,.orcontainer for the electric heating element, is passed, such vessel beingpreferably of tulullar shape, open at the topand provided with a flangewhereby it will rest upon the cover era flange thereon to support thevessel within .the tank. The hcati. element vessel or container is.proyidcd with a suitable cover that rests upon the flange and may berigidly secured thereto by any suitable means. Pendant from thecover ofthe elernentvessel are a pair of insulated. rods that support and act asleads to an electrical heating element of the exp cd ty the upper endsof such rods b.,.ig' connected tofiany convenient source of electricsupply.

points inthe element vessel below the rnial water level, when the vesselis po- .icned within the tank, are two short pro jOCtiilQf tubesintegral with or rigidly stcured -to the vessel, such tubes acting as aninlet and an outlet, the inlet being below and of a smaller (li.. ;neterthan are outlet. In operation when the tank is filled or nearly so thewater will flow into the element vessel and submerge the exposed heatingelement, the heat from which will cause the water to circulate from thevessel to the tank and vice versa when the electric current is switchedon.

In the accompanying drawings- Fig. 1 is a perspective view (partly insection) of a heater constructed according to my invention.

Fig. 2 is a central vertical sectional elevation of the applianceasshown at Fig. -1

cylindrical in shape. Between It-he inner vertical wall 10 and the outervertical wall it a coiled tube 12, of suitable metal and diameter, issecured, .the upper end of the coil. passing inwardly through the wall.of the container and the lower .end outwardly through the wall of thejacket. Secured .to the inwardly projecting end ,of the coil 12- ie anordinary lfloat controlled valve .13. The position of the earthenware"heating element container 14 however will not, .(in the smaller sizes)permit a straight float lever to be used and in order to overcome thatdifficulty a short lever 15 may be rigidly secured to or formed integralwith a metal hoop 1.6 of suitable shape and measurement so that thelatter may surround .the con tainer and the float 17 be secured to thehoop at a point diametrically opposite to the'short lever 15. in thismanner the float may operate the float lever without causing the hoop 16to foul the earthenware coir tainer 14. The space between the walls 10and 11 and the bottonilll and 11 of the container and its jacket ispacked with .a suitable insulating material, preferably silica wool 18and the container provided with an outlet pipe 19 that is controlled bya cock 20. "The annular space at the top of the walls 10 and 11 isclosed in any suitable manner and the orifices in the walls 10 and 11through which the pipes pass will be made water tight either bysoldering the pipes to the respective walls or the pipes may be screwthreaded and be secured by nuts and back nuts a manner commonly adoptedfor similar purposes.

The jacketed container will be closed "by a hollow annular lid or cover21 that is packed with suitable material, preferably silica wool 18 andwhich is provided with a flange 22 projecting inwardly from the bottomof its inner vertical wall. It is preferable that this flange 22 shouldbe bent so that it will lie below the bottom of the packed lid 21thereby enabling the terminals 23 and vent 2a to lie within the centralcircular space 25 without projecting above the upper surface of the lid21.

The electrical heating element 26 is of the exposed type of any suitabledesign and when in operation will be immersed in the water within thespecially constructed earthenware vessel 1 t, which is preferablycylindrical in shape and .is provided with a flange 27, one or moreoutlet passages 28 near the top and one or more inlet passages 29 nearthe bottom. hese inlet and outlet passages are for the purpose ofallowing the water to circulate from the heating element container tothe main container and at the same time to increase the ohmic resistanceand thereby reduce the leakage of current from the ele meat 26 to thewater within the main container. In order that the passages shall be ofsufficientlength, at the same time maintaining the strength of thecontainer and ensuring that those parts in which the passages are formedshall not project too far the vessel is provided with a suitable numberof suitably shaped lugs 30 the passages 28 and 29 being formen in therespective lugs 30 with a downward and outward inclination as is clearlyshown at Fig. 2 of the drawings. The cross sectional area of the inletpassage or passages 29 should be somewhat smaller than the outletpassage or passages 28 to ensure that there shall be no chokage in thecirculation of the water from the earthenware container to the maintank. In practice it will generally be found that one inlet conduit 29and one outlet conduit 28 will be sufficient as the combined crosssectional area of these openings must be small enough to produce thenecessary ohmic resistance. It the combined cross sectional area ofthose conduits is too great leakage will occur and danger may ensue.

The vessel 1% is passed downwardly through the central opening in thecover 21 until its flange 2T rests upon the flange 22. A suitablejointing ring 31 will be interposed between the flanges 22 and 27 and a'disc 32 of suitable material placed upon the flange 27 and the wholethen secured together by a suitable number of bolts and nuts 33.

The heating element 26 may be suspended at the lower ends of two metalrods 34-34 which serve as the electric current leads, the upper ends ofsuch rods being screw threaded so that they may be secured to the disc.

32 by the nuts 35 and terminals 23. It is preferable that the rods orleads 343d should be electrically insulated and for that purpose theymay each be passed through a close fitting glass tube 36. The terminals23 will be connected to the respective leads from any convenient sourceof electric current supply according to general electric practice.

In the manufacture of the vessel 14 it may be found advantageous to formit so that instead of there being individual lugs 30 that formation willbe continued right round the vessel in order to form upper and lowerannular shoulders as will be seen by referring to 3O at Fig. 1 of thedrawings, and the required number of tubular conduits formed in thoseannular shoulders.

I claiml. An electric water heater of the character -describedincluding, a double-walled storage tank, an annular lid for said tank,an annular supporting flange projecting from the inner edge of the lid,an earthenware vessel provided with an outwardly extending annularflange for engagement with the flange on the lid for suspending thevessel within the tank, the wall of the vessel being provided withopenings for establishing communication with the tank, a cover disk forthe vessel, electric heating elements suspended from the disk andarranged within the vessel, a coil arranged between the walls of thetank and in connection with a water supply, a float valve arranged inthe upper part of the tank and connected with the upper end of the coil,and a valved controlled outlet leading from the bottom of the tank.

2. In an electric water heater as claimed in claim 1, wherein the wallsof the earthenware vessel adjacent the upper and lower ends of the sameare thickened while the openings which establish communication be tweenthe vessel and the tank are arranged through the thickened portions ofthe wall at an inclination so as to increase the ohmic resistance andreduce the leakage of current from the heating elements to the waterwitlr in the tank.

3. An electric heater as claimed in claim 1, wherein the lid for thetank is recessed centrally above the supporting flange, the supportingflange being also extended downwardly so that when the earthenwarevessel and the heating elements connections are attached to the diskthey lie below the upper surface of the lid.

In testimony whereof, I have signed my name to this specification.

ALFRED EMILE LElVIS.

